UN Secretary-general Ban Ki-moon on Tuesday reiterated the need for world leaders to deliver sizable financial support to developing countries to fund their efforts in mitigating and adapting to climate change.

"Climate financing is an investment in a safer, cleaner, more prosperous future for all of us," Ban said in remarks at a press conference in New York, marking the end of a two-day meeting of the high- level Advisory Group on Climate Change Financing (AGF).

Launched by the secretary-general in February 2010, the advisory group will seek to identify long-term financial resources for climate change.

Sources of long-term financing "must be economically sound and politically viable," Ban told reporters.

The AGF is also tasked with mobilizing delivery of the funds that were pledged at the 2009 Copenhagen conference, where world leaders agreed to scale up support to reach 100 billion U.S. dollars by 2020 -- in addition to 30 billion dollars by 2012.

"Delivery on these pledges is essential, it strengthens trust between developing and developed countries," said Ban. "It is crucial for building positive momentum in the global negotiations. "

The AGF comprises 21 principal members including heads of state, ministers, private sector officials, along with experts on public finance and development.

"Climate change is not going away, the risks and costs of inaction grow each year. The more we delay, the more we have to pay in lost opportunities, resources and lives -- that is why this advisory group is so important," Ban said.

The advisory group is expected to submit its final recommendations on practical solutions financing in developing countries in October.

"We are confident we will submit a very robust report," AGF co- chair and Ethiopian Prime Minister Meles Zenawi told reporters at the press conference.

The report will feed into the UN Framework Convention on Climate Change, in time for the Conference of the Parties that is set to take place in Cancun, Mexico.